Backwater control device for sewers



y 1958 o. STEINBERG BACKWATEER CQNTROL DEVICE FOR SEWERS Filed July 2, 1956 Inventor 01m STEINBERG 7161a... dbmb "3* United States Patent BACKWATER (IONTROL DEVICE FOR SEWERS Otto Steinberg, Plainview, Tex.

Application July 2, 1956, Serial No. 595,244

4 Claims. (Cl. 137-423) This invention relates to devices for preventing water from backing up out of sewers into homes or other buildmgs.

One principal object of the invention is to provide a new and improved device that will positively prevent reverse flow of backwater above a predetermined level at the sewer outlet of a building.

A further object is to provide a new and improved backwater .control device having means providing double safety against the rising of backwater.

Another object is to provide a new and improved backwater control device having means for discharging normal drainage into the sewer when the backwater has risen to such an extent that the backwater control feature of the device has gone into action.

Thus, it is an object of the present invention to prevent reverse flow of backwater while providing for disposal of normal drainage.

It is another object to provide such a new and improved backwater control device which is unusually simple in construction and low in cost.

Further objects and advantages of the present invention will appear from the following description, taken with the accompanying drawing, in which the single figure is a diagrammatic elevational sectional view showing a backwater control device which constitutes an illustrative embodiment of the invention.

The illustrated backwater control device comprises an inlet or first chamber 12, adapted to receive normal drainage from a building or the like, together with an outlet chamber 14 adapted to be connected to a sewer main. The backwater control device 10 also preferably includes an intermediate or second chamber 16 which is interposed between the first and third chambers 12 and 14. In this instance, all three chambers 12, 14 and 16 are formed by a single tank 18, rather than a series of tanks, which might be provided. First and second partitions 20 and 22 divide the tank into the three chambers. Thus the first partition 20 is between the first and second chambers 12 and 16, while the second partition 22 is between the second and third chambers 16 and 14. The three chambers 12, 16 and 14 have bottom walls 24, 26 and 28 which are at successively lower levels to provide for normal drainage by gravity. A single, removable top wall or cover 30 closes the upper ends of all three compartments. In the usual installation, the cover 30 is approximately flush with the lowermost floor of the building, usually the basement floor.

An inlet pipe stub 32 leads into the first compartment 12 and is adapted to be connected to the drainage system of the building or the like, for receiving the drainage therefrom. In like manner, an outlet pipe stub 34 leads out of the outlet compartment 14 and is adapted to be connected to the sewer line.

Between the first and second compartments 12 and 16, there is an opening 36 which extends through the partition 20. A pipe stub or ring 38 is mounted in the second com- 2,844,163 Patented July 22, 1958 ice partment 16 around the opening 36 to provide a valve seat 40 facing into the compartment 16.

There is also an opening 42 extending through the partition 22 between the second and third compartments 16 and 14. A pipe stub or ring 44 is mounted around the opening 42 to provide a valve seat 46 facing into the third compartment 14.

The openings 36 and 42 are adapted to be closed by float valve mechanisms 48 and 50, which are essentially 74 and 76.

the same in construction. Thus, only the intermediate float valve 48 need bedescribed in detail. The components of the outlet float valve 50 will be given the same reference characters as applied to the corresponding components of the intermediate float valve 48, with the addition of the suflix a. In this way, the description of the intermediate float valve 48 may readily be read upon the outlet float valve 50. It will be seen that the intermediate float valve 48 is equipped with a valve plate 52 faced with a sheet or plate 54 of synthetic rubber or other soft, resilient material. The rubber-faced plate 52 is adapted to move against the valve seat 40 so as to form a seal therewith and thereby close oif the opening 36. I

The valve plate 52 is mounted for swinging movement toward and away from the valve seat 40. In this instance, the plate 52 is carried by a flexible spring arm 56 which is swingably suppo-rted at its upper end by a pivot 58, the lower end of the arm being connected to the center of the valve plate by a bolt 60 or the like.

To actuate the valve plate 52, the valve mechanism 48 is equipped with a float 62, connected to the valve plate 52 by means of a parallelogram linkage 64. Thus, the float 62 is mounted on a vertically movable bar or member 66 which carries upper and lower vertically aligned pivots 68 and 70. A fixed member 72 carries fixed upper and lower pivots 74 and 76 which also are vertically aligned. Upper and lower parallel links 78 and 80 extend between the movable member 66 and the fixed pivots More specifically, the upper link 78 is connected between the pivots 68 and 74, while the lower link 80 is connected between the pivots and 76. One of the links, in this case the lower link 80, has a lever arm 82 extending away from the float 62 and beyond the pivot 76. A link 84 is pivotally connected between the arm 82 and a bracket 86 which is carried by the valve supporting arm 56. Thus, upward movement of the float 62 tends to close the valve plate 52, while downward movement of the float is effective to open the valve plate. The weight of the float 62 and the parallelogram linkage 64 is made suflicient to bias the valve plate 52 to its open position, in the absence of backwater.

It will be noted that the valve mechanism 50 in the outlet chamber 14 is on a lower level than the valve mechanism 48 in the intermediate chamber 16. If any water backs up from the sewer into the chambers 14 and 16, the rising backwater will reach the float 62a in the outlet chamber 14 before it reaches the float in the intermediate chamber 16. Accordingly, the valve plate 52a in the outlet chamber 14 will be closed before the valve plate in the intermediate chamber 16. Closure of the outlet valve plate 52a will ordinarily prevent any further reverse flow of backwater into the intermediate chamber 16. Thus, under the usual backwater conditions, the outlet valve 52a will close, while the intermediate valve will remain open.

However, there is some chance that sticks, stones or other debris may become caught between the outlet valve member 52a and its seat 46. In that case, the backwater will leak past the outlet valve 52a into the intermediate chamber 16. Accordingly, the backwater will continue to rise in the chamber 16 and will cause closure of the intermediate valve 52. Thus, the two valves 52 and 52a'provide a double safety factor. If

either of the valves functions normally, the reverse flow of backwater into the inlet chamber will be arrested.

Provision is made for disposing of drainage when either or both of the float valves 52 and 52a are closed.-

that the discharge end of the discharge conduit 90 is substantially above the level of'the opening 42 through which drainage normally flowsinto the outlet compartment 14 when the valves 52 and 52a are open. Thus, the drainage water passes'through-the discharge conduit 90 only when the pump 88 is operating. The pump 88 easily develops enough-pressure to prevent backwater from travelling into the inlet chamber 12 through'the discharge conduit 90. Moreover, the pump 88 is easily able to force the drainagewaterinto the outlet chamber 14 against any backwater pressure that may exist therein. i

In the operation of the backwater control device 10, the valves 52 and 52a are normally biased to their open positions by the weight of the floats 62 and 62a and the linkages 64 and 64a. The drainage from the building or the like enters the inlet chamber12 through the inlet connection 32 and normally flows through the connecting opening 36, the intermediate chamber 16, the connecting opening 42, the outlet chamber 14, and the outlet connection 34, into the sewer.

Under flood conditions, water may back up from the sewer. However, the control device 10 prevents the backwater from rising to an objectionable level at the inlet connection 32. The rising backwater in the outlet chamber 14 lifts the float62a and closes the outlet valve 52a before the backwater reaches an objectionable level. Ordinarily, the valve 52a closes completely before'the backwater rises to a sufficiently high level to close the intermediate valve 52. However, if the outlet valve 52a should leak or should be held in a partly open position for any reason, the intermediate valve 52a will be closed by its float 62 before the backwater rises objectionably in the inlet chamber 12. Thus, the two valves 52 and 52a provide a double safety factor.

When either or both of the valves 52 and 52a are closed, the drainage water can no longer flow into the sewer by gravity. Accordingly, it tends to accumulate in the inlet chamber 12. However, the sump pump 88 is effective to withdraw drainage from the inlet chamber 12 and to discharge the drainage into the outlet chamber 14, against any backwater pressure that may exsit therein. The pump 88 also prevents any backwater from passing into the inlet chamber 12 through the discharge conduit '90 of the pump.

It will be recognized that thebackwater control device is effective in operation. It provides a high degree of safety against reverse flow of backwater. Moreover, the backwater control device is unusually simple in construction and low in cost. The entire device may readily be serviced by removing the cover 30.

Various modifications, alternative constructions and equivalents may be employed without departing from the true spirit and scope of the invention as exemplified in the foregoing description and defined in the following claims.

I claim:

1. In a backwater control device for sewers, the combination comprising means defining first, second and third substantially closed chambers, inlet means leading into said first chamber forreceiving drainage, first connecting means extending between said first and second chambers for carrying the drainage therebetween, second connecting 'means extending between said second and third chambers for carrying the drainage therebetween,

outletmeans leading from said third chamber and adapt-' ed to be connected to a sewer for carrying the drainage therebetween, and first and second float valves biased to open positions and movable to closed positions for closing said first and second connecting means respectively in response to the rising of backwater to predetermined levels in said second and third chambers, said second float valve being disposed at a substantially lower level than said first float valve and thereby being effective to close prior to closure of said first valve, said first float valve being effective to close in the event that backwater should continue to rise in said second chamber due to leakage past said second valve.

2. In a backwater control device for sewers,-the combination comprising means defining first and second substantially closed chambers, inlet means leading into said first chamber for receiving drainage, connecting means extending between said first and second chambers for carrying drainage therebetween, outlet means leading from said second chamber and adapted to be connected to a sewer for carrying drainage therebetween, said con necting means defining a valve seat facing into said second chamber, a valve plate movable against and away from said valve seat, a flexible spring arm having its upper end pivotally supported and its lower end connected to said valve plate for swingably supporting said valve plate, a parallelogram linkage including a first pair of fixed horizontal pivots disposed one above the other, a movable vertical member carrying a second pair of horizontal pivots disposed one above the other, upper and lower parallel linksextending between the upper and lower pivots of said pairs and supporting said vertical member for vertical movement, said links being disposed above the level of said valve plate, one of said links having a lever arm rigidly connected thereto and swingable therewith about the corresponding pivot of said first pair, an additional link connected between the outer end of said lever arm and said spring arm and extending downwardly therebetween, and a float mounted on said vertical member and effective to close said valve plate in response to the rising ofbackwater in said second chamber to a predetermined level, the weight of said linkage and said float being effective to bias said valve plate away from said valve seat to open position, said additional link being connected to an intermediate point on said spring arm to fiexsaid spring arm and thereby apply spring pressure to said valve plate.

3. In a backwater control device for sewers, the combination comprising a tank'having a pair of partitions defining first, second and third compartments therein, means defining an inlet opening leading into said first compartment for receiving drainage, means defining a second opening extending through one of said partitions between said first and second compartments for carrying the drainage therebetween, means defining a third opening extending through the other of said partitions between said second and third compartments to carry the drainage therebetween, means defining an outlet opening leading from said third compartment and adapted to be connected to a sewer main to carry the drainage out of said third compartment, first valve seat means around said second opening and facing into said second compartment, a swingable valve plate movable against and away from said first valve seat means, an operating mechanism connected to said valve plate and yieldably biasing said valve plate away from said first valve seat means, said mechanism including a float located in said second compartment and effective to close said valve plate against said first valve seat means in response to the rising of backwater in said second compartment to a predetermined level, second valve seat means around said third opening and facing into said third compartment, a second valve plate swingable against and away from said second valve seat means, and a'second actuating mechanism connected to said second valve plate and yieldably biasing said second valve plate away from said second valve seat means, said second mechanism including a second float located in said third compartment and eflective to close said second valve plate against said second valve seat means in response to the rising of backwater in said third compartment to a predetermined level, said second float being disposed at a substantially lower level than said first mentioned float and thereby being effective to close said second valve plate prior to closure of said first valve plate, said first float being operative to close said first valve plate in the event that backwater should leak past said second valve plate.

4. In a backwater control device for sewers, the combination comprising means defining first, second and third substantially closed chambers, inlet means leading into said first chamber for receiving drainage, first connecting means extending between said first and second chambers for carrying the drainage therebetween, second connecting means extending between said second and third chambers for carrying the drainage therebetween, outlet means leading from said third chamber and adapted to be connected to a sewer for carrying the drainage thereto, said first and second connecting means defining respective first and second valve seats facing into said second and third chambers, first and second valve plates movable against and away from said respective first and second valve seats, each of said valve plates being provided with a flexible spring arm having its upper end pivotally supported and its lower end connected to said valve plate for swingably supporting said valve plate, first and second floats disposed inside said second and third chambers for closing said valve plates in response to the rising of backwater therein,

and first first and second parallelogram linkages connected between said respective first and second floats and said first and second valves plates, each of said linkages including a first pair of fixed horizontal pivots disposed one 6 above the other, a movable vertical member rigidly secured to the corresponding float and carrying a second pair of horizontal pivots disposed one above the other, upper and lower parallel generally horizontal links extending between the upper and lower pivots of said pairs and supporting said vertical member and the corresponding float for vertical movement, said links being disposed above the level of the corresponding valve plate, one of said links having a lever arm rigidly connected thereto and swingable therewith about the corresponding pivot of said first pair, and an additional link connected between said lever arm and said spring arm of the corresponding valve plate and extending downwardly therebetween, said additional link being connected to an intermediate point on the corresponding spring arm to flex said spring arm and thereby applyspring pressure to said valve plate, the weight of each linkage and float being effective to bias the corresponding valve plate away from said valve seat to open position, said second float being disposed at a substantially lower level than said first float and thereby being efiective' to close said second valve plate prior to closure of said first valve plate, said first float being operative to close said first valve plate in the event that backwater should leak past said second valve plate.

References Cited in the file of this patent UNITED STATES PATENTS 1,488,604 Lawton Apr. 1, 1924 2,310,677 Campbell Feb. 9, 1943 2,431,640 Gordon Nov. 25, 1947 2,695,072 Hauslein Nov. 23, 1954 2,739,662 Sofia Mar. 27, 1956 FOREIGN PATENTS 248,033 Germany June 13, 1912 

